In recent years as the resolution and the speed of image capturing apparatuses become higher, the capacity of flash memories become greater and image processing circuits of image processing apparatuses become higher in speed and lower in power, long-time moving image capturing and long-time moving image playback at a high resolution are becoming possible.
However, in some cases such as when the user is not capturing images intentionally at the time of moving image capturing, and when moving images are captured for a long period of time so as not to miss anything in capturing, many unnecessary moving image frames are included in the moving images after capturing. Then, it puts a big load on the editing work and playback work as post-processes, which may decrease the efficiency of the editing work and playback work of moving images. For example, when many unnecessary moving image frames are included in a moving image file, it takes a large amount of troubles and time to find the desired moving image frame, and it takes a large amount of time to load the moving image file onto the editing program and the playback program.
For example, there is a technique to, when editing and playing back moving images, determine a moving image frame with a small amount of gradation change as an unnecessary moving image frame, in the respective moving image frames of a moving image file, and to delete the moving image frame automatically (for example, see Patent documents 1-3).
[Patent document 1] Japanese Laid-open Patent Publication No. 2008-182544
[Patent document 2] Japanese Laid-open Patent Publication No. 2005-295285
[Patent document 3] Japanese Laid-open Patent Publication No. 2000-209483